Managing Insulin Pumps for Exercise (Study 2)

NCT01398995 | Terminated

• 1 other identifier: RXQ404
• Study Type: interventional
• Target: 6
• Locations: 1 country
• Sites: 1

Brief Summary

People with Type 1 Diabetes Mellitus (T1DM) like to take part in sport and exercise, but problems with metabolism and blood glucose control can make this difficult. Some people with T1DM administer their insulin via an insulin pump, also know as continuous subcutaneous insulin infusion (CSII) therapy, in which a background or basal level of insulin is constantly infused under the skin by a special pump, with bolus doses of insulin given to accompany food. Clinical experience suggests that this may be particularly useful for managing diabetes for exercise, but there is limited experimental evidence to support this. The aim of this research , which is divided into three parts, is to investigate the hypothesis that the physiological response to sub-maximal (moderate) exercise of a person with type 1 diabetes treated with CSII, can be made to approximate more closely to the physiological response of a healthy individual by a prior reduction of their basal insulin infusion rate. Evidence from children demonstrates that reducing the basal insulin infusion rate to 50% of normal at the beginning of exercise can reduce rates of low blood glucose (hypoglycaemia) during exercise. However, reducing the insulin infusion rate will not have an immediate effect on levels of insulin in the body, and evidence from adults suggests that the level of insulin in the bloodstream at the start of exercise is an important factor in whether hypoglycaemia develops during exercise. This suggests that reducing the basal insulin infusion rate some time before exercise may be useful. The aim of this study is to compare the effect of a basal insulin reduction on blood glucose levels between visits when this reduction is made at the start of exercise, 30 minutes before, 60 minutes before and 90 minutes before. The null hypothesis to be tested is that there is no difference between these conditions.

Conditions

Type 1 Diabetes

Keywords

Type 1 Diabetes; Exercise; continuous subcutaneous insulin infusion

Outcome Measures

Primary Outcomes (1)

• Comparison of glucose excursion (change in blood glucose) between baseline and the end of exercise between the four conditions.

  Samples taken on arrival and at the end of exercise

Secondary Outcomes (4)

• Comparison between the four conditions of change in blood glucose levels between baseline and the beginning of exercise, and between the beginning and end of exercise.

  Samples taken at baseline, beginning and end of exercise

• Levels of NEFA and lactate will be compared between the four conditions

  Samples will be taken at the 6 time points detailed below

• Correlation between levels of NEFA and lactate and blood glucose will be considered.

  Samples will be taken at the time points detailed below

• Ratio of respiratory quotient (RQ) at the beginning of exercise to RQ at the end of exercise compared between the four conditions.

  Breath by breath data will be recorded for 2 minutes at the start and the end of the exercise period

Study Arms (4)

90 minutes

EXPERIMENTAL

Basal insulin infusion reduced to 50% of normal 90 minutes prior to exercise

Other: Reduction of basal insulin infusion to 50% of normal

60 minutes

EXPERIMENTAL

Basal insulin infusion reduced to 50% of normal 60 minutes prior to exercise

Other: Reduction of basal insulin infusion to 50% of normal

30 minutes

EXPERIMENTAL

Basal insulin infusion reduced to normal 30 minutes prior to exercise

Other: Reduction of basal insulin infusion to 50% of normal

Start

EXPERIMENTAL

Basal insulin infusion reduced to 50% of normal at the start of exercise

Other: Reduction of basal insulin infusion to 50% of normal

Interventions

Reduction of basal insulin infusion to 50% of normal OTHER

Each participant in this cross-over trial will participate in the 4 arms of the trial. They will be presented with the four conditions in randomised order - reducing their basal insulin infusion rate to 50% of normal at the four time points specified. A comparison will be made between the conditions.

30 minutes; 60 minutes; 90 minutes; Start

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Participant is willing and able to give informed consent for participation in the study.
• Male or Female, aged between 18 and 65 years
• Diagnosed with Type 1 diabetes mellitus
• Treated with CSII for at least 3 months
• Exercises regularly for more than 1 hour per week

You may not qualify if:

• People with any one of the following complications of diabetes:
• stage 2+ diabetic retinopathy
• renal impairment (with creatinine \>150micromol/l)
• known history or symptoms of cardiovascular disease
• foot ulceration
• peripheral vascular disease
• Known pregnancy or breastfeeding
• Untreated or unstable respiratory disease
• Known hypoglycaemia unawareness
• Treatment with drugs known to interfere with glucose metabolism

Sponsors & Collaborators

• Buckinghamshire Healthcare NHS Trust: lead
• Animas Corporation: collaborator

Study Sites (1)

Wycombe Hospital

High Wycombe, Buckinghamshire, HP11 2TT, United Kingdom

Location

MeSH Terms

Conditions

Diabetes Mellitus, Type 1; Motor Activity

Condition Hierarchy (Ancestors)

Diabetes Mellitus; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Endocrine System Diseases; Autoimmune Diseases; Immune System Diseases; Behavior

Study Officials

• Ian W Gallen, MD FRCP

  Buckinghamshire Healthcare NHS Trust

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER

Study Record Dates

• First Submitted: July 20, 2011
• First Posted: July 21, 2011
• Study Start: May 1, 2011
• Primary Completion: September 1, 2011
• Study Completion: September 1, 2011
• Last Updated: July 21, 2011

Record last verified: 2011-07

Locations

GB (1)